1. Technical Field
This invention relates to a replacement drop sprinkler assembly for connection to an irrigation conduit of a center pivot irrigation system and, more particularly, to a replacement drop sprinkler assembly adapted to be connected to the irrigation conduit of a center pivot irrigation system adjacent a tower support of the system, the assembly including a fluid conduit, a valve having an inlet and two outlets and two sprinkler conduits extending from the valve such that fluid outflow from the sprinkler conduits is directed forward or rearward of the wheels of the center pivot irrigation system.
2. Description of the Prior Art
The advent of irrigation systems has allowed for the use of much land which was previously unusable for the farming of crops. As the demand for produce has increased, use of irrigation systems has likewise increased. Irrigation systems are now used on all types of terrain and in many types of soils.
Center pivot irrigation systems have steadily become the standard apparatus for irrigating crops. This type of irrigation system was originally designed to be used on farmland where the center pivot irrigation system could make a complete circuit of the property. Therefore, early center pivot irrigation systems were designed to travel only in a clockwise or counterclockwise direction, there being no need to provide a reversing mechanism for the irrigation system. More recently however, center pivot irrigation systems have been used in areas which require the system to be able to reverse to avoid obstacles such as wetlands or property boundaries.
Another popular modification to the standard center pivot irrigation system is to replace the standard above-pipeline sprinklers with low pressure revolving or spray nozzles on drops. A drop is a fluid conduit which extends from the main irrigation conduit downwards towards the ground, thus bringing the nozzle closer to the ground to prevent evaporation of the irrigation water before contact with crops is achieved. Adjacent each of the wheeled towers, however, a standard drop will not function correctly, as the tower structure impedes proper distribution of water from the nozzle. Instead, center pivot irrigation systems are commonly fitted what are known as "boom backs", which are fluid conduits which extend downwardly and rearwardly from the main irrigation conduit and end in a sprinkler position behind the rearmost wheel of the irrigation tower. This allows the sprinkler to dispense water without the sprinkler pattern being disrupted by the tower structure. Use of such a "boom back" is therefore acceptable with center pivot irrigation systems traveling only in a single direction.
When a standard boom back is used on a center pivot irrigation system which is capable of reversing direction, however, when the system is reversed, water from the boom back nozzle is distributed directly in front of the leading wheel of the irrigation tower. Because the wheel is effectively tracking through newly formed mud, the resulting wheel rut is substantially deeper than the rut produced by the wheel traveling over dry ground. Therefore, it is highly undesirable for the sprinkler system to dispense water in front of the leading wheel of an irrigation tower. Furthermore, because standard boom backs utilize 360.degree. nozzles, the adjacent tower support wheel is sprayed with some amount of water, which is undesirable. Therefore, there is a need for a directional sprinkler which will prevent water from being deposited on the surface of the tower support wheel.
While various examples from the prior art disclose nozzles which project water rearwards of the irrigation system (see Kinkead, U.S. Pat. No. 3,493,176, Dejoie et al., U.S. Pat. No. 4,363,444, and Paul, U.S. Pat. No. 3,589,604), none of these devices address and solve the problems encountered when a reversible center pivot irrigation system is used.
Therefore, an object of the present invention is to provide an approved replacement drop sprinkler apparatus.
Another object of the present invention is to provide a replacement pump sprinkler assembly which includes a fluid conduit connected to the main irrigation conduit, a two-way valve connected to the opposite end of the fluid conduit, and a pair of irrigation conduits, one extending downwardly and forwardly and the other extending downwardly and rearwardly such that water may be ejected forwardly or rearwardly of the center pivot irrigation system depending on the direction of motion of the system.
Another object of the present invention is to provide a replacement drop sprinkler assembly which may be quickly and easily installed on a variety of types of center pivot irrigation system systems.
Another object of the present invention is to provide a replacement drop sprinkler assembly which will project water forwards or rearwards of the irrigation tower wheels while preventing substantial amounts of water from accumulating on the wheel surfaces.
Another object of the present invention is to provide a replacement drop sprinkler assembly which will assist in the prevention of deep wheel ruts caused by irrigation system wheels tracking through newly formed mud.
Finally, an object of the present invention is to provide a replacement drop sprinkler assembly which is relatively simple to manufacture and is safe in use.